Data Suggests RNAi May Be Used to Fight
Mad Cow, Other Prion Diseases in Livestock
Researchers this week published data in the Proceedings of the National Academy of Sciences suggesting that RNAi might be used to produce transgenic livestock resistant to prion disease such as bovine spongiform encepholopathy.
According to the PNAS paper, the researchers designed short hairpin RNAs that suppress caprine and bovine prion protein (PrP). Lentiviral vectors were used to deliver a transgene expressing the shRNAs into goat fibroblasts.
"These cells were then used for nuclear transplantation to produce a cloned goat fetus, which was surgically recovered at 81 days of gestation and compared with an age-matched control derived by natural mating," the paper's abstract states. "All tissues examined in the cloned fetus expressed GFP, and PCR analysis confirmed the presence of the transgene encoding the PrP shRNA. Most relevant, Western blot analysis performed on brain tissues comparing the transgenic fetus with control demonstrated a significant decrease in PrP expression levels."
To confirm that this process could be used with cows, recombinant virus was injected into the perivitelline space of bovine ova. Following in vitro fertilization and culture, 76 percent of the blastocysts "exhibited GFP expression, indicative that they expressed shRNAs targeting PrP," the abstract states.
The PNAS paper was co-authored by researchers from Cold Spring Harbor Laboratory and Texas A&M University.
Intradigm Inks Manufacturing Deal with Omnia
Intradigm said this week that it has signed a master services agreement with Omnia Biologics for process development and cGMP manufacturing services.
Intradigm said that the deal is expected to accelerate its development of its RNAi clinical development programs.
Terms of the arrangement were not disclosed.
Intradigm is currently developing ICS-283, a preclinical siRNA-based therapy for cancer. Officials from the company did not return requests for comment on the status of the program.